1 /* 2 * TCP over IPv6 3 * Linux INET6 implementation 4 * 5 * Authors: 6 * Pedro Roque <roque@di.fc.ul.pt> 7 * 8 * Based on: 9 * linux/net/ipv4/tcp.c 10 * linux/net/ipv4/tcp_input.c 11 * linux/net/ipv4/tcp_output.c 12 * 13 * Fixes: 14 * Hideaki YOSHIFUJI : sin6_scope_id support 15 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which 16 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind 17 * a single port at the same time. 18 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/tcp6 to seq_file. 19 * 20 * This program is free software; you can redistribute it and/or 21 * modify it under the terms of the GNU General Public License 22 * as published by the Free Software Foundation; either version 23 * 2 of the License, or (at your option) any later version. 24 */ 25 26 #include <linux/bottom_half.h> 27 #include <linux/module.h> 28 #include <linux/errno.h> 29 #include <linux/types.h> 30 #include <linux/socket.h> 31 #include <linux/sockios.h> 32 #include <linux/net.h> 33 #include <linux/jiffies.h> 34 #include <linux/in.h> 35 #include <linux/in6.h> 36 #include <linux/netdevice.h> 37 #include <linux/init.h> 38 #include <linux/jhash.h> 39 #include <linux/ipsec.h> 40 #include <linux/times.h> 41 #include <linux/slab.h> 42 43 #include <linux/ipv6.h> 44 #include <linux/icmpv6.h> 45 #include <linux/random.h> 46 47 #include <net/tcp.h> 48 #include <net/ndisc.h> 49 #include <net/inet6_hashtables.h> 50 #include <net/inet6_connection_sock.h> 51 #include <net/ipv6.h> 52 #include <net/transp_v6.h> 53 #include <net/addrconf.h> 54 #include <net/ip6_route.h> 55 #include <net/ip6_checksum.h> 56 #include <net/inet_ecn.h> 57 #include <net/protocol.h> 58 #include <net/xfrm.h> 59 #include <net/snmp.h> 60 #include <net/dsfield.h> 61 #include <net/timewait_sock.h> 62 #include <net/netdma.h> 63 #include <net/inet_common.h> 64 #include <net/secure_seq.h> 65 #include <net/tcp_memcontrol.h> 66 67 #include <asm/uaccess.h> 68 69 #include <linux/proc_fs.h> 70 #include <linux/seq_file.h> 71 72 #include <linux/crypto.h> 73 #include <linux/scatterlist.h> 74 75 static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb); 76 static void tcp_v6_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, 77 struct request_sock *req); 78 79 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb); 80 static void __tcp_v6_send_check(struct sk_buff *skb, 81 const struct in6_addr *saddr, 82 const struct in6_addr *daddr); 83 84 static const struct inet_connection_sock_af_ops ipv6_mapped; 85 static const struct inet_connection_sock_af_ops ipv6_specific; 86 #ifdef CONFIG_TCP_MD5SIG 87 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific; 88 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific; 89 #else 90 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(struct sock *sk, 91 const struct in6_addr *addr) 92 { 93 return NULL; 94 } 95 #endif 96 97 static void tcp_v6_hash(struct sock *sk) 98 { 99 if (sk->sk_state != TCP_CLOSE) { 100 if (inet_csk(sk)->icsk_af_ops == &ipv6_mapped) { 101 tcp_prot.hash(sk); 102 return; 103 } 104 local_bh_disable(); 105 __inet6_hash(sk, NULL); 106 local_bh_enable(); 107 } 108 } 109 110 static __inline__ __sum16 tcp_v6_check(int len, 111 const struct in6_addr *saddr, 112 const struct in6_addr *daddr, 113 __wsum base) 114 { 115 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base); 116 } 117 118 static __u32 tcp_v6_init_sequence(const struct sk_buff *skb) 119 { 120 return secure_tcpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32, 121 ipv6_hdr(skb)->saddr.s6_addr32, 122 tcp_hdr(skb)->dest, 123 tcp_hdr(skb)->source); 124 } 125 126 static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, 127 int addr_len) 128 { 129 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; 130 struct inet_sock *inet = inet_sk(sk); 131 struct inet_connection_sock *icsk = inet_csk(sk); 132 struct ipv6_pinfo *np = inet6_sk(sk); 133 struct tcp_sock *tp = tcp_sk(sk); 134 struct in6_addr *saddr = NULL, *final_p, final; 135 struct rt6_info *rt; 136 struct flowi6 fl6; 137 struct dst_entry *dst; 138 int addr_type; 139 int err; 140 141 if (addr_len < SIN6_LEN_RFC2133) 142 return -EINVAL; 143 144 if (usin->sin6_family != AF_INET6) 145 return -EAFNOSUPPORT; 146 147 memset(&fl6, 0, sizeof(fl6)); 148 149 if (np->sndflow) { 150 fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK; 151 IP6_ECN_flow_init(fl6.flowlabel); 152 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) { 153 struct ip6_flowlabel *flowlabel; 154 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 155 if (flowlabel == NULL) 156 return -EINVAL; 157 usin->sin6_addr = flowlabel->dst; 158 fl6_sock_release(flowlabel); 159 } 160 } 161 162 /* 163 * connect() to INADDR_ANY means loopback (BSD'ism). 164 */ 165 166 if(ipv6_addr_any(&usin->sin6_addr)) 167 usin->sin6_addr.s6_addr[15] = 0x1; 168 169 addr_type = ipv6_addr_type(&usin->sin6_addr); 170 171 if(addr_type & IPV6_ADDR_MULTICAST) 172 return -ENETUNREACH; 173 174 if (addr_type&IPV6_ADDR_LINKLOCAL) { 175 if (addr_len >= sizeof(struct sockaddr_in6) && 176 usin->sin6_scope_id) { 177 /* If interface is set while binding, indices 178 * must coincide. 179 */ 180 if (sk->sk_bound_dev_if && 181 sk->sk_bound_dev_if != usin->sin6_scope_id) 182 return -EINVAL; 183 184 sk->sk_bound_dev_if = usin->sin6_scope_id; 185 } 186 187 /* Connect to link-local address requires an interface */ 188 if (!sk->sk_bound_dev_if) 189 return -EINVAL; 190 } 191 192 if (tp->rx_opt.ts_recent_stamp && 193 !ipv6_addr_equal(&np->daddr, &usin->sin6_addr)) { 194 tp->rx_opt.ts_recent = 0; 195 tp->rx_opt.ts_recent_stamp = 0; 196 tp->write_seq = 0; 197 } 198 199 np->daddr = usin->sin6_addr; 200 np->flow_label = fl6.flowlabel; 201 202 /* 203 * TCP over IPv4 204 */ 205 206 if (addr_type == IPV6_ADDR_MAPPED) { 207 u32 exthdrlen = icsk->icsk_ext_hdr_len; 208 struct sockaddr_in sin; 209 210 SOCK_DEBUG(sk, "connect: ipv4 mapped\n"); 211 212 if (__ipv6_only_sock(sk)) 213 return -ENETUNREACH; 214 215 sin.sin_family = AF_INET; 216 sin.sin_port = usin->sin6_port; 217 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3]; 218 219 icsk->icsk_af_ops = &ipv6_mapped; 220 sk->sk_backlog_rcv = tcp_v4_do_rcv; 221 #ifdef CONFIG_TCP_MD5SIG 222 tp->af_specific = &tcp_sock_ipv6_mapped_specific; 223 #endif 224 225 err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin)); 226 227 if (err) { 228 icsk->icsk_ext_hdr_len = exthdrlen; 229 icsk->icsk_af_ops = &ipv6_specific; 230 sk->sk_backlog_rcv = tcp_v6_do_rcv; 231 #ifdef CONFIG_TCP_MD5SIG 232 tp->af_specific = &tcp_sock_ipv6_specific; 233 #endif 234 goto failure; 235 } else { 236 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr); 237 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, 238 &np->rcv_saddr); 239 } 240 241 return err; 242 } 243 244 if (!ipv6_addr_any(&np->rcv_saddr)) 245 saddr = &np->rcv_saddr; 246 247 fl6.flowi6_proto = IPPROTO_TCP; 248 fl6.daddr = np->daddr; 249 fl6.saddr = saddr ? *saddr : np->saddr; 250 fl6.flowi6_oif = sk->sk_bound_dev_if; 251 fl6.flowi6_mark = sk->sk_mark; 252 fl6.fl6_dport = usin->sin6_port; 253 fl6.fl6_sport = inet->inet_sport; 254 255 final_p = fl6_update_dst(&fl6, np->opt, &final); 256 257 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); 258 259 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, true); 260 if (IS_ERR(dst)) { 261 err = PTR_ERR(dst); 262 goto failure; 263 } 264 265 if (saddr == NULL) { 266 saddr = &fl6.saddr; 267 np->rcv_saddr = *saddr; 268 } 269 270 /* set the source address */ 271 np->saddr = *saddr; 272 inet->inet_rcv_saddr = LOOPBACK4_IPV6; 273 274 sk->sk_gso_type = SKB_GSO_TCPV6; 275 __ip6_dst_store(sk, dst, NULL, NULL); 276 277 rt = (struct rt6_info *) dst; 278 if (tcp_death_row.sysctl_tw_recycle && 279 !tp->rx_opt.ts_recent_stamp && 280 ipv6_addr_equal(&rt->rt6i_dst.addr, &np->daddr)) { 281 struct inet_peer *peer = rt6_get_peer(rt); 282 /* 283 * VJ's idea. We save last timestamp seen from 284 * the destination in peer table, when entering state 285 * TIME-WAIT * and initialize rx_opt.ts_recent from it, 286 * when trying new connection. 287 */ 288 if (peer) { 289 inet_peer_refcheck(peer); 290 if ((u32)get_seconds() - peer->tcp_ts_stamp <= TCP_PAWS_MSL) { 291 tp->rx_opt.ts_recent_stamp = peer->tcp_ts_stamp; 292 tp->rx_opt.ts_recent = peer->tcp_ts; 293 } 294 } 295 } 296 297 icsk->icsk_ext_hdr_len = 0; 298 if (np->opt) 299 icsk->icsk_ext_hdr_len = (np->opt->opt_flen + 300 np->opt->opt_nflen); 301 302 tp->rx_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr); 303 304 inet->inet_dport = usin->sin6_port; 305 306 tcp_set_state(sk, TCP_SYN_SENT); 307 err = inet6_hash_connect(&tcp_death_row, sk); 308 if (err) 309 goto late_failure; 310 311 if (!tp->write_seq) 312 tp->write_seq = secure_tcpv6_sequence_number(np->saddr.s6_addr32, 313 np->daddr.s6_addr32, 314 inet->inet_sport, 315 inet->inet_dport); 316 317 err = tcp_connect(sk); 318 if (err) 319 goto late_failure; 320 321 return 0; 322 323 late_failure: 324 tcp_set_state(sk, TCP_CLOSE); 325 __sk_dst_reset(sk); 326 failure: 327 inet->inet_dport = 0; 328 sk->sk_route_caps = 0; 329 return err; 330 } 331 332 static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 333 u8 type, u8 code, int offset, __be32 info) 334 { 335 const struct ipv6hdr *hdr = (const struct ipv6hdr*)skb->data; 336 const struct tcphdr *th = (struct tcphdr *)(skb->data+offset); 337 struct ipv6_pinfo *np; 338 struct sock *sk; 339 int err; 340 struct tcp_sock *tp; 341 __u32 seq; 342 struct net *net = dev_net(skb->dev); 343 344 sk = inet6_lookup(net, &tcp_hashinfo, &hdr->daddr, 345 th->dest, &hdr->saddr, th->source, skb->dev->ifindex); 346 347 if (sk == NULL) { 348 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev), 349 ICMP6_MIB_INERRORS); 350 return; 351 } 352 353 if (sk->sk_state == TCP_TIME_WAIT) { 354 inet_twsk_put(inet_twsk(sk)); 355 return; 356 } 357 358 bh_lock_sock(sk); 359 if (sock_owned_by_user(sk)) 360 NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS); 361 362 if (sk->sk_state == TCP_CLOSE) 363 goto out; 364 365 if (ipv6_hdr(skb)->hop_limit < inet6_sk(sk)->min_hopcount) { 366 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); 367 goto out; 368 } 369 370 tp = tcp_sk(sk); 371 seq = ntohl(th->seq); 372 if (sk->sk_state != TCP_LISTEN && 373 !between(seq, tp->snd_una, tp->snd_nxt)) { 374 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); 375 goto out; 376 } 377 378 np = inet6_sk(sk); 379 380 if (type == ICMPV6_PKT_TOOBIG) { 381 struct dst_entry *dst; 382 383 if (sock_owned_by_user(sk)) 384 goto out; 385 if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) 386 goto out; 387 388 /* icmp should have updated the destination cache entry */ 389 dst = __sk_dst_check(sk, np->dst_cookie); 390 391 if (dst == NULL) { 392 struct inet_sock *inet = inet_sk(sk); 393 struct flowi6 fl6; 394 395 /* BUGGG_FUTURE: Again, it is not clear how 396 to handle rthdr case. Ignore this complexity 397 for now. 398 */ 399 memset(&fl6, 0, sizeof(fl6)); 400 fl6.flowi6_proto = IPPROTO_TCP; 401 fl6.daddr = np->daddr; 402 fl6.saddr = np->saddr; 403 fl6.flowi6_oif = sk->sk_bound_dev_if; 404 fl6.flowi6_mark = sk->sk_mark; 405 fl6.fl6_dport = inet->inet_dport; 406 fl6.fl6_sport = inet->inet_sport; 407 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6)); 408 409 dst = ip6_dst_lookup_flow(sk, &fl6, NULL, false); 410 if (IS_ERR(dst)) { 411 sk->sk_err_soft = -PTR_ERR(dst); 412 goto out; 413 } 414 415 } else 416 dst_hold(dst); 417 418 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) { 419 tcp_sync_mss(sk, dst_mtu(dst)); 420 tcp_simple_retransmit(sk); 421 } /* else let the usual retransmit timer handle it */ 422 dst_release(dst); 423 goto out; 424 } 425 426 icmpv6_err_convert(type, code, &err); 427 428 /* Might be for an request_sock */ 429 switch (sk->sk_state) { 430 struct request_sock *req, **prev; 431 case TCP_LISTEN: 432 if (sock_owned_by_user(sk)) 433 goto out; 434 435 req = inet6_csk_search_req(sk, &prev, th->dest, &hdr->daddr, 436 &hdr->saddr, inet6_iif(skb)); 437 if (!req) 438 goto out; 439 440 /* ICMPs are not backlogged, hence we cannot get 441 * an established socket here. 442 */ 443 WARN_ON(req->sk != NULL); 444 445 if (seq != tcp_rsk(req)->snt_isn) { 446 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); 447 goto out; 448 } 449 450 inet_csk_reqsk_queue_drop(sk, req, prev); 451 goto out; 452 453 case TCP_SYN_SENT: 454 case TCP_SYN_RECV: /* Cannot happen. 455 It can, it SYNs are crossed. --ANK */ 456 if (!sock_owned_by_user(sk)) { 457 sk->sk_err = err; 458 sk->sk_error_report(sk); /* Wake people up to see the error (see connect in sock.c) */ 459 460 tcp_done(sk); 461 } else 462 sk->sk_err_soft = err; 463 goto out; 464 } 465 466 if (!sock_owned_by_user(sk) && np->recverr) { 467 sk->sk_err = err; 468 sk->sk_error_report(sk); 469 } else 470 sk->sk_err_soft = err; 471 472 out: 473 bh_unlock_sock(sk); 474 sock_put(sk); 475 } 476 477 478 static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req, 479 struct request_values *rvp) 480 { 481 struct inet6_request_sock *treq = inet6_rsk(req); 482 struct ipv6_pinfo *np = inet6_sk(sk); 483 struct sk_buff * skb; 484 struct ipv6_txoptions *opt = NULL; 485 struct in6_addr * final_p, final; 486 struct flowi6 fl6; 487 struct dst_entry *dst; 488 int err; 489 490 memset(&fl6, 0, sizeof(fl6)); 491 fl6.flowi6_proto = IPPROTO_TCP; 492 fl6.daddr = treq->rmt_addr; 493 fl6.saddr = treq->loc_addr; 494 fl6.flowlabel = 0; 495 fl6.flowi6_oif = treq->iif; 496 fl6.flowi6_mark = sk->sk_mark; 497 fl6.fl6_dport = inet_rsk(req)->rmt_port; 498 fl6.fl6_sport = inet_rsk(req)->loc_port; 499 security_req_classify_flow(req, flowi6_to_flowi(&fl6)); 500 501 opt = np->opt; 502 final_p = fl6_update_dst(&fl6, opt, &final); 503 504 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false); 505 if (IS_ERR(dst)) { 506 err = PTR_ERR(dst); 507 dst = NULL; 508 goto done; 509 } 510 skb = tcp_make_synack(sk, dst, req, rvp); 511 err = -ENOMEM; 512 if (skb) { 513 __tcp_v6_send_check(skb, &treq->loc_addr, &treq->rmt_addr); 514 515 fl6.daddr = treq->rmt_addr; 516 err = ip6_xmit(sk, skb, &fl6, opt, np->tclass); 517 err = net_xmit_eval(err); 518 } 519 520 done: 521 if (opt && opt != np->opt) 522 sock_kfree_s(sk, opt, opt->tot_len); 523 dst_release(dst); 524 return err; 525 } 526 527 static int tcp_v6_rtx_synack(struct sock *sk, struct request_sock *req, 528 struct request_values *rvp) 529 { 530 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS); 531 return tcp_v6_send_synack(sk, req, rvp); 532 } 533 534 static void tcp_v6_reqsk_destructor(struct request_sock *req) 535 { 536 kfree_skb(inet6_rsk(req)->pktopts); 537 } 538 539 #ifdef CONFIG_TCP_MD5SIG 540 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(struct sock *sk, 541 const struct in6_addr *addr) 542 { 543 return tcp_md5_do_lookup(sk, (union tcp_md5_addr *)addr, AF_INET6); 544 } 545 546 static struct tcp_md5sig_key *tcp_v6_md5_lookup(struct sock *sk, 547 struct sock *addr_sk) 548 { 549 return tcp_v6_md5_do_lookup(sk, &inet6_sk(addr_sk)->daddr); 550 } 551 552 static struct tcp_md5sig_key *tcp_v6_reqsk_md5_lookup(struct sock *sk, 553 struct request_sock *req) 554 { 555 return tcp_v6_md5_do_lookup(sk, &inet6_rsk(req)->rmt_addr); 556 } 557 558 static int tcp_v6_parse_md5_keys (struct sock *sk, char __user *optval, 559 int optlen) 560 { 561 struct tcp_md5sig cmd; 562 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd.tcpm_addr; 563 564 if (optlen < sizeof(cmd)) 565 return -EINVAL; 566 567 if (copy_from_user(&cmd, optval, sizeof(cmd))) 568 return -EFAULT; 569 570 if (sin6->sin6_family != AF_INET6) 571 return -EINVAL; 572 573 if (!cmd.tcpm_keylen) { 574 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) 575 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], 576 AF_INET); 577 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr, 578 AF_INET6); 579 } 580 581 if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) 582 return -EINVAL; 583 584 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) 585 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], 586 AF_INET, cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); 587 588 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr, 589 AF_INET6, cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); 590 } 591 592 static int tcp_v6_md5_hash_pseudoheader(struct tcp_md5sig_pool *hp, 593 const struct in6_addr *daddr, 594 const struct in6_addr *saddr, int nbytes) 595 { 596 struct tcp6_pseudohdr *bp; 597 struct scatterlist sg; 598 599 bp = &hp->md5_blk.ip6; 600 /* 1. TCP pseudo-header (RFC2460) */ 601 bp->saddr = *saddr; 602 bp->daddr = *daddr; 603 bp->protocol = cpu_to_be32(IPPROTO_TCP); 604 bp->len = cpu_to_be32(nbytes); 605 606 sg_init_one(&sg, bp, sizeof(*bp)); 607 return crypto_hash_update(&hp->md5_desc, &sg, sizeof(*bp)); 608 } 609 610 static int tcp_v6_md5_hash_hdr(char *md5_hash, struct tcp_md5sig_key *key, 611 const struct in6_addr *daddr, struct in6_addr *saddr, 612 const struct tcphdr *th) 613 { 614 struct tcp_md5sig_pool *hp; 615 struct hash_desc *desc; 616 617 hp = tcp_get_md5sig_pool(); 618 if (!hp) 619 goto clear_hash_noput; 620 desc = &hp->md5_desc; 621 622 if (crypto_hash_init(desc)) 623 goto clear_hash; 624 if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, th->doff << 2)) 625 goto clear_hash; 626 if (tcp_md5_hash_header(hp, th)) 627 goto clear_hash; 628 if (tcp_md5_hash_key(hp, key)) 629 goto clear_hash; 630 if (crypto_hash_final(desc, md5_hash)) 631 goto clear_hash; 632 633 tcp_put_md5sig_pool(); 634 return 0; 635 636 clear_hash: 637 tcp_put_md5sig_pool(); 638 clear_hash_noput: 639 memset(md5_hash, 0, 16); 640 return 1; 641 } 642 643 static int tcp_v6_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key, 644 const struct sock *sk, 645 const struct request_sock *req, 646 const struct sk_buff *skb) 647 { 648 const struct in6_addr *saddr, *daddr; 649 struct tcp_md5sig_pool *hp; 650 struct hash_desc *desc; 651 const struct tcphdr *th = tcp_hdr(skb); 652 653 if (sk) { 654 saddr = &inet6_sk(sk)->saddr; 655 daddr = &inet6_sk(sk)->daddr; 656 } else if (req) { 657 saddr = &inet6_rsk(req)->loc_addr; 658 daddr = &inet6_rsk(req)->rmt_addr; 659 } else { 660 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 661 saddr = &ip6h->saddr; 662 daddr = &ip6h->daddr; 663 } 664 665 hp = tcp_get_md5sig_pool(); 666 if (!hp) 667 goto clear_hash_noput; 668 desc = &hp->md5_desc; 669 670 if (crypto_hash_init(desc)) 671 goto clear_hash; 672 673 if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, skb->len)) 674 goto clear_hash; 675 if (tcp_md5_hash_header(hp, th)) 676 goto clear_hash; 677 if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2)) 678 goto clear_hash; 679 if (tcp_md5_hash_key(hp, key)) 680 goto clear_hash; 681 if (crypto_hash_final(desc, md5_hash)) 682 goto clear_hash; 683 684 tcp_put_md5sig_pool(); 685 return 0; 686 687 clear_hash: 688 tcp_put_md5sig_pool(); 689 clear_hash_noput: 690 memset(md5_hash, 0, 16); 691 return 1; 692 } 693 694 static int tcp_v6_inbound_md5_hash(struct sock *sk, const struct sk_buff *skb) 695 { 696 const __u8 *hash_location = NULL; 697 struct tcp_md5sig_key *hash_expected; 698 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 699 const struct tcphdr *th = tcp_hdr(skb); 700 int genhash; 701 u8 newhash[16]; 702 703 hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr); 704 hash_location = tcp_parse_md5sig_option(th); 705 706 /* We've parsed the options - do we have a hash? */ 707 if (!hash_expected && !hash_location) 708 return 0; 709 710 if (hash_expected && !hash_location) { 711 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); 712 return 1; 713 } 714 715 if (!hash_expected && hash_location) { 716 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); 717 return 1; 718 } 719 720 /* check the signature */ 721 genhash = tcp_v6_md5_hash_skb(newhash, 722 hash_expected, 723 NULL, NULL, skb); 724 725 if (genhash || memcmp(hash_location, newhash, 16) != 0) { 726 net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n", 727 genhash ? "failed" : "mismatch", 728 &ip6h->saddr, ntohs(th->source), 729 &ip6h->daddr, ntohs(th->dest)); 730 return 1; 731 } 732 return 0; 733 } 734 #endif 735 736 struct request_sock_ops tcp6_request_sock_ops __read_mostly = { 737 .family = AF_INET6, 738 .obj_size = sizeof(struct tcp6_request_sock), 739 .rtx_syn_ack = tcp_v6_rtx_synack, 740 .send_ack = tcp_v6_reqsk_send_ack, 741 .destructor = tcp_v6_reqsk_destructor, 742 .send_reset = tcp_v6_send_reset, 743 .syn_ack_timeout = tcp_syn_ack_timeout, 744 }; 745 746 #ifdef CONFIG_TCP_MD5SIG 747 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { 748 .md5_lookup = tcp_v6_reqsk_md5_lookup, 749 .calc_md5_hash = tcp_v6_md5_hash_skb, 750 }; 751 #endif 752 753 static void __tcp_v6_send_check(struct sk_buff *skb, 754 const struct in6_addr *saddr, const struct in6_addr *daddr) 755 { 756 struct tcphdr *th = tcp_hdr(skb); 757 758 if (skb->ip_summed == CHECKSUM_PARTIAL) { 759 th->check = ~tcp_v6_check(skb->len, saddr, daddr, 0); 760 skb->csum_start = skb_transport_header(skb) - skb->head; 761 skb->csum_offset = offsetof(struct tcphdr, check); 762 } else { 763 th->check = tcp_v6_check(skb->len, saddr, daddr, 764 csum_partial(th, th->doff << 2, 765 skb->csum)); 766 } 767 } 768 769 static void tcp_v6_send_check(struct sock *sk, struct sk_buff *skb) 770 { 771 struct ipv6_pinfo *np = inet6_sk(sk); 772 773 __tcp_v6_send_check(skb, &np->saddr, &np->daddr); 774 } 775 776 static int tcp_v6_gso_send_check(struct sk_buff *skb) 777 { 778 const struct ipv6hdr *ipv6h; 779 struct tcphdr *th; 780 781 if (!pskb_may_pull(skb, sizeof(*th))) 782 return -EINVAL; 783 784 ipv6h = ipv6_hdr(skb); 785 th = tcp_hdr(skb); 786 787 th->check = 0; 788 skb->ip_summed = CHECKSUM_PARTIAL; 789 __tcp_v6_send_check(skb, &ipv6h->saddr, &ipv6h->daddr); 790 return 0; 791 } 792 793 static struct sk_buff **tcp6_gro_receive(struct sk_buff **head, 794 struct sk_buff *skb) 795 { 796 const struct ipv6hdr *iph = skb_gro_network_header(skb); 797 798 switch (skb->ip_summed) { 799 case CHECKSUM_COMPLETE: 800 if (!tcp_v6_check(skb_gro_len(skb), &iph->saddr, &iph->daddr, 801 skb->csum)) { 802 skb->ip_summed = CHECKSUM_UNNECESSARY; 803 break; 804 } 805 806 /* fall through */ 807 case CHECKSUM_NONE: 808 NAPI_GRO_CB(skb)->flush = 1; 809 return NULL; 810 } 811 812 return tcp_gro_receive(head, skb); 813 } 814 815 static int tcp6_gro_complete(struct sk_buff *skb) 816 { 817 const struct ipv6hdr *iph = ipv6_hdr(skb); 818 struct tcphdr *th = tcp_hdr(skb); 819 820 th->check = ~tcp_v6_check(skb->len - skb_transport_offset(skb), 821 &iph->saddr, &iph->daddr, 0); 822 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6; 823 824 return tcp_gro_complete(skb); 825 } 826 827 static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win, 828 u32 ts, struct tcp_md5sig_key *key, int rst, u8 tclass) 829 { 830 const struct tcphdr *th = tcp_hdr(skb); 831 struct tcphdr *t1; 832 struct sk_buff *buff; 833 struct flowi6 fl6; 834 struct net *net = dev_net(skb_dst(skb)->dev); 835 struct sock *ctl_sk = net->ipv6.tcp_sk; 836 unsigned int tot_len = sizeof(struct tcphdr); 837 struct dst_entry *dst; 838 __be32 *topt; 839 840 if (ts) 841 tot_len += TCPOLEN_TSTAMP_ALIGNED; 842 #ifdef CONFIG_TCP_MD5SIG 843 if (key) 844 tot_len += TCPOLEN_MD5SIG_ALIGNED; 845 #endif 846 847 buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len, 848 GFP_ATOMIC); 849 if (buff == NULL) 850 return; 851 852 skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len); 853 854 t1 = (struct tcphdr *) skb_push(buff, tot_len); 855 skb_reset_transport_header(buff); 856 857 /* Swap the send and the receive. */ 858 memset(t1, 0, sizeof(*t1)); 859 t1->dest = th->source; 860 t1->source = th->dest; 861 t1->doff = tot_len / 4; 862 t1->seq = htonl(seq); 863 t1->ack_seq = htonl(ack); 864 t1->ack = !rst || !th->ack; 865 t1->rst = rst; 866 t1->window = htons(win); 867 868 topt = (__be32 *)(t1 + 1); 869 870 if (ts) { 871 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 872 (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); 873 *topt++ = htonl(tcp_time_stamp); 874 *topt++ = htonl(ts); 875 } 876 877 #ifdef CONFIG_TCP_MD5SIG 878 if (key) { 879 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 880 (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG); 881 tcp_v6_md5_hash_hdr((__u8 *)topt, key, 882 &ipv6_hdr(skb)->saddr, 883 &ipv6_hdr(skb)->daddr, t1); 884 } 885 #endif 886 887 memset(&fl6, 0, sizeof(fl6)); 888 fl6.daddr = ipv6_hdr(skb)->saddr; 889 fl6.saddr = ipv6_hdr(skb)->daddr; 890 891 buff->ip_summed = CHECKSUM_PARTIAL; 892 buff->csum = 0; 893 894 __tcp_v6_send_check(buff, &fl6.saddr, &fl6.daddr); 895 896 fl6.flowi6_proto = IPPROTO_TCP; 897 fl6.flowi6_oif = inet6_iif(skb); 898 fl6.fl6_dport = t1->dest; 899 fl6.fl6_sport = t1->source; 900 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6)); 901 902 /* Pass a socket to ip6_dst_lookup either it is for RST 903 * Underlying function will use this to retrieve the network 904 * namespace 905 */ 906 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL, false); 907 if (!IS_ERR(dst)) { 908 skb_dst_set(buff, dst); 909 ip6_xmit(ctl_sk, buff, &fl6, NULL, tclass); 910 TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS); 911 if (rst) 912 TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS); 913 return; 914 } 915 916 kfree_skb(buff); 917 } 918 919 static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb) 920 { 921 const struct tcphdr *th = tcp_hdr(skb); 922 u32 seq = 0, ack_seq = 0; 923 struct tcp_md5sig_key *key = NULL; 924 #ifdef CONFIG_TCP_MD5SIG 925 const __u8 *hash_location = NULL; 926 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 927 unsigned char newhash[16]; 928 int genhash; 929 struct sock *sk1 = NULL; 930 #endif 931 932 if (th->rst) 933 return; 934 935 if (!ipv6_unicast_destination(skb)) 936 return; 937 938 #ifdef CONFIG_TCP_MD5SIG 939 hash_location = tcp_parse_md5sig_option(th); 940 if (!sk && hash_location) { 941 /* 942 * active side is lost. Try to find listening socket through 943 * source port, and then find md5 key through listening socket. 944 * we are not loose security here: 945 * Incoming packet is checked with md5 hash with finding key, 946 * no RST generated if md5 hash doesn't match. 947 */ 948 sk1 = inet6_lookup_listener(dev_net(skb_dst(skb)->dev), 949 &tcp_hashinfo, &ipv6h->daddr, 950 ntohs(th->source), inet6_iif(skb)); 951 if (!sk1) 952 return; 953 954 rcu_read_lock(); 955 key = tcp_v6_md5_do_lookup(sk1, &ipv6h->saddr); 956 if (!key) 957 goto release_sk1; 958 959 genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, NULL, skb); 960 if (genhash || memcmp(hash_location, newhash, 16) != 0) 961 goto release_sk1; 962 } else { 963 key = sk ? tcp_v6_md5_do_lookup(sk, &ipv6h->saddr) : NULL; 964 } 965 #endif 966 967 if (th->ack) 968 seq = ntohl(th->ack_seq); 969 else 970 ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len - 971 (th->doff << 2); 972 973 tcp_v6_send_response(skb, seq, ack_seq, 0, 0, key, 1, 0); 974 975 #ifdef CONFIG_TCP_MD5SIG 976 release_sk1: 977 if (sk1) { 978 rcu_read_unlock(); 979 sock_put(sk1); 980 } 981 #endif 982 } 983 984 static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts, 985 struct tcp_md5sig_key *key, u8 tclass) 986 { 987 tcp_v6_send_response(skb, seq, ack, win, ts, key, 0, tclass); 988 } 989 990 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) 991 { 992 struct inet_timewait_sock *tw = inet_twsk(sk); 993 struct tcp_timewait_sock *tcptw = tcp_twsk(sk); 994 995 tcp_v6_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, 996 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, 997 tcptw->tw_ts_recent, tcp_twsk_md5_key(tcptw), 998 tw->tw_tclass); 999 1000 inet_twsk_put(tw); 1001 } 1002 1003 static void tcp_v6_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, 1004 struct request_sock *req) 1005 { 1006 tcp_v6_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, req->ts_recent, 1007 tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr), 0); 1008 } 1009 1010 1011 static struct sock *tcp_v6_hnd_req(struct sock *sk,struct sk_buff *skb) 1012 { 1013 struct request_sock *req, **prev; 1014 const struct tcphdr *th = tcp_hdr(skb); 1015 struct sock *nsk; 1016 1017 /* Find possible connection requests. */ 1018 req = inet6_csk_search_req(sk, &prev, th->source, 1019 &ipv6_hdr(skb)->saddr, 1020 &ipv6_hdr(skb)->daddr, inet6_iif(skb)); 1021 if (req) 1022 return tcp_check_req(sk, skb, req, prev); 1023 1024 nsk = __inet6_lookup_established(sock_net(sk), &tcp_hashinfo, 1025 &ipv6_hdr(skb)->saddr, th->source, 1026 &ipv6_hdr(skb)->daddr, ntohs(th->dest), inet6_iif(skb)); 1027 1028 if (nsk) { 1029 if (nsk->sk_state != TCP_TIME_WAIT) { 1030 bh_lock_sock(nsk); 1031 return nsk; 1032 } 1033 inet_twsk_put(inet_twsk(nsk)); 1034 return NULL; 1035 } 1036 1037 #ifdef CONFIG_SYN_COOKIES 1038 if (!th->syn) 1039 sk = cookie_v6_check(sk, skb); 1040 #endif 1041 return sk; 1042 } 1043 1044 /* FIXME: this is substantially similar to the ipv4 code. 1045 * Can some kind of merge be done? -- erics 1046 */ 1047 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) 1048 { 1049 struct tcp_extend_values tmp_ext; 1050 struct tcp_options_received tmp_opt; 1051 const u8 *hash_location; 1052 struct request_sock *req; 1053 struct inet6_request_sock *treq; 1054 struct ipv6_pinfo *np = inet6_sk(sk); 1055 struct tcp_sock *tp = tcp_sk(sk); 1056 __u32 isn = TCP_SKB_CB(skb)->when; 1057 struct dst_entry *dst = NULL; 1058 bool want_cookie = false; 1059 1060 if (skb->protocol == htons(ETH_P_IP)) 1061 return tcp_v4_conn_request(sk, skb); 1062 1063 if (!ipv6_unicast_destination(skb)) 1064 goto drop; 1065 1066 if (inet_csk_reqsk_queue_is_full(sk) && !isn) { 1067 want_cookie = tcp_syn_flood_action(sk, skb, "TCPv6"); 1068 if (!want_cookie) 1069 goto drop; 1070 } 1071 1072 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) 1073 goto drop; 1074 1075 req = inet6_reqsk_alloc(&tcp6_request_sock_ops); 1076 if (req == NULL) 1077 goto drop; 1078 1079 #ifdef CONFIG_TCP_MD5SIG 1080 tcp_rsk(req)->af_specific = &tcp_request_sock_ipv6_ops; 1081 #endif 1082 1083 tcp_clear_options(&tmp_opt); 1084 tmp_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr); 1085 tmp_opt.user_mss = tp->rx_opt.user_mss; 1086 tcp_parse_options(skb, &tmp_opt, &hash_location, 0); 1087 1088 if (tmp_opt.cookie_plus > 0 && 1089 tmp_opt.saw_tstamp && 1090 !tp->rx_opt.cookie_out_never && 1091 (sysctl_tcp_cookie_size > 0 || 1092 (tp->cookie_values != NULL && 1093 tp->cookie_values->cookie_desired > 0))) { 1094 u8 *c; 1095 u32 *d; 1096 u32 *mess = &tmp_ext.cookie_bakery[COOKIE_DIGEST_WORDS]; 1097 int l = tmp_opt.cookie_plus - TCPOLEN_COOKIE_BASE; 1098 1099 if (tcp_cookie_generator(&tmp_ext.cookie_bakery[0]) != 0) 1100 goto drop_and_free; 1101 1102 /* Secret recipe starts with IP addresses */ 1103 d = (__force u32 *)&ipv6_hdr(skb)->daddr.s6_addr32[0]; 1104 *mess++ ^= *d++; 1105 *mess++ ^= *d++; 1106 *mess++ ^= *d++; 1107 *mess++ ^= *d++; 1108 d = (__force u32 *)&ipv6_hdr(skb)->saddr.s6_addr32[0]; 1109 *mess++ ^= *d++; 1110 *mess++ ^= *d++; 1111 *mess++ ^= *d++; 1112 *mess++ ^= *d++; 1113 1114 /* plus variable length Initiator Cookie */ 1115 c = (u8 *)mess; 1116 while (l-- > 0) 1117 *c++ ^= *hash_location++; 1118 1119 want_cookie = false; /* not our kind of cookie */ 1120 tmp_ext.cookie_out_never = 0; /* false */ 1121 tmp_ext.cookie_plus = tmp_opt.cookie_plus; 1122 } else if (!tp->rx_opt.cookie_in_always) { 1123 /* redundant indications, but ensure initialization. */ 1124 tmp_ext.cookie_out_never = 1; /* true */ 1125 tmp_ext.cookie_plus = 0; 1126 } else { 1127 goto drop_and_free; 1128 } 1129 tmp_ext.cookie_in_always = tp->rx_opt.cookie_in_always; 1130 1131 if (want_cookie && !tmp_opt.saw_tstamp) 1132 tcp_clear_options(&tmp_opt); 1133 1134 tmp_opt.tstamp_ok = tmp_opt.saw_tstamp; 1135 tcp_openreq_init(req, &tmp_opt, skb); 1136 1137 treq = inet6_rsk(req); 1138 treq->rmt_addr = ipv6_hdr(skb)->saddr; 1139 treq->loc_addr = ipv6_hdr(skb)->daddr; 1140 if (!want_cookie || tmp_opt.tstamp_ok) 1141 TCP_ECN_create_request(req, skb); 1142 1143 treq->iif = sk->sk_bound_dev_if; 1144 1145 /* So that link locals have meaning */ 1146 if (!sk->sk_bound_dev_if && 1147 ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL) 1148 treq->iif = inet6_iif(skb); 1149 1150 if (!isn) { 1151 struct inet_peer *peer = NULL; 1152 1153 if (ipv6_opt_accepted(sk, skb) || 1154 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo || 1155 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) { 1156 atomic_inc(&skb->users); 1157 treq->pktopts = skb; 1158 } 1159 1160 if (want_cookie) { 1161 isn = cookie_v6_init_sequence(sk, skb, &req->mss); 1162 req->cookie_ts = tmp_opt.tstamp_ok; 1163 goto have_isn; 1164 } 1165 1166 /* VJ's idea. We save last timestamp seen 1167 * from the destination in peer table, when entering 1168 * state TIME-WAIT, and check against it before 1169 * accepting new connection request. 1170 * 1171 * If "isn" is not zero, this request hit alive 1172 * timewait bucket, so that all the necessary checks 1173 * are made in the function processing timewait state. 1174 */ 1175 if (tmp_opt.saw_tstamp && 1176 tcp_death_row.sysctl_tw_recycle && 1177 (dst = inet6_csk_route_req(sk, req)) != NULL && 1178 (peer = rt6_get_peer((struct rt6_info *)dst)) != NULL && 1179 ipv6_addr_equal((struct in6_addr *)peer->daddr.addr.a6, 1180 &treq->rmt_addr)) { 1181 inet_peer_refcheck(peer); 1182 if ((u32)get_seconds() - peer->tcp_ts_stamp < TCP_PAWS_MSL && 1183 (s32)(peer->tcp_ts - req->ts_recent) > 1184 TCP_PAWS_WINDOW) { 1185 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_PAWSPASSIVEREJECTED); 1186 goto drop_and_release; 1187 } 1188 } 1189 /* Kill the following clause, if you dislike this way. */ 1190 else if (!sysctl_tcp_syncookies && 1191 (sysctl_max_syn_backlog - inet_csk_reqsk_queue_len(sk) < 1192 (sysctl_max_syn_backlog >> 2)) && 1193 (!peer || !peer->tcp_ts_stamp) && 1194 (!dst || !dst_metric(dst, RTAX_RTT))) { 1195 /* Without syncookies last quarter of 1196 * backlog is filled with destinations, 1197 * proven to be alive. 1198 * It means that we continue to communicate 1199 * to destinations, already remembered 1200 * to the moment of synflood. 1201 */ 1202 LIMIT_NETDEBUG(KERN_DEBUG "TCP: drop open request from %pI6/%u\n", 1203 &treq->rmt_addr, ntohs(tcp_hdr(skb)->source)); 1204 goto drop_and_release; 1205 } 1206 1207 isn = tcp_v6_init_sequence(skb); 1208 } 1209 have_isn: 1210 tcp_rsk(req)->snt_isn = isn; 1211 tcp_rsk(req)->snt_synack = tcp_time_stamp; 1212 1213 security_inet_conn_request(sk, skb, req); 1214 1215 if (tcp_v6_send_synack(sk, req, 1216 (struct request_values *)&tmp_ext) || 1217 want_cookie) 1218 goto drop_and_free; 1219 1220 inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); 1221 return 0; 1222 1223 drop_and_release: 1224 dst_release(dst); 1225 drop_and_free: 1226 reqsk_free(req); 1227 drop: 1228 return 0; /* don't send reset */ 1229 } 1230 1231 static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb, 1232 struct request_sock *req, 1233 struct dst_entry *dst) 1234 { 1235 struct inet6_request_sock *treq; 1236 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 1237 struct tcp6_sock *newtcp6sk; 1238 struct inet_sock *newinet; 1239 struct tcp_sock *newtp; 1240 struct sock *newsk; 1241 struct ipv6_txoptions *opt; 1242 #ifdef CONFIG_TCP_MD5SIG 1243 struct tcp_md5sig_key *key; 1244 #endif 1245 1246 if (skb->protocol == htons(ETH_P_IP)) { 1247 /* 1248 * v6 mapped 1249 */ 1250 1251 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst); 1252 1253 if (newsk == NULL) 1254 return NULL; 1255 1256 newtcp6sk = (struct tcp6_sock *)newsk; 1257 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1258 1259 newinet = inet_sk(newsk); 1260 newnp = inet6_sk(newsk); 1261 newtp = tcp_sk(newsk); 1262 1263 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1264 1265 ipv6_addr_set_v4mapped(newinet->inet_daddr, &newnp->daddr); 1266 1267 ipv6_addr_set_v4mapped(newinet->inet_saddr, &newnp->saddr); 1268 1269 newnp->rcv_saddr = newnp->saddr; 1270 1271 inet_csk(newsk)->icsk_af_ops = &ipv6_mapped; 1272 newsk->sk_backlog_rcv = tcp_v4_do_rcv; 1273 #ifdef CONFIG_TCP_MD5SIG 1274 newtp->af_specific = &tcp_sock_ipv6_mapped_specific; 1275 #endif 1276 1277 newnp->ipv6_ac_list = NULL; 1278 newnp->ipv6_fl_list = NULL; 1279 newnp->pktoptions = NULL; 1280 newnp->opt = NULL; 1281 newnp->mcast_oif = inet6_iif(skb); 1282 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1283 newnp->rcv_tclass = ipv6_tclass(ipv6_hdr(skb)); 1284 1285 /* 1286 * No need to charge this sock to the relevant IPv6 refcnt debug socks count 1287 * here, tcp_create_openreq_child now does this for us, see the comment in 1288 * that function for the gory details. -acme 1289 */ 1290 1291 /* It is tricky place. Until this moment IPv4 tcp 1292 worked with IPv6 icsk.icsk_af_ops. 1293 Sync it now. 1294 */ 1295 tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie); 1296 1297 return newsk; 1298 } 1299 1300 treq = inet6_rsk(req); 1301 opt = np->opt; 1302 1303 if (sk_acceptq_is_full(sk)) 1304 goto out_overflow; 1305 1306 if (!dst) { 1307 dst = inet6_csk_route_req(sk, req); 1308 if (!dst) 1309 goto out; 1310 } 1311 1312 newsk = tcp_create_openreq_child(sk, req, skb); 1313 if (newsk == NULL) 1314 goto out_nonewsk; 1315 1316 /* 1317 * No need to charge this sock to the relevant IPv6 refcnt debug socks 1318 * count here, tcp_create_openreq_child now does this for us, see the 1319 * comment in that function for the gory details. -acme 1320 */ 1321 1322 newsk->sk_gso_type = SKB_GSO_TCPV6; 1323 __ip6_dst_store(newsk, dst, NULL, NULL); 1324 1325 newtcp6sk = (struct tcp6_sock *)newsk; 1326 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1327 1328 newtp = tcp_sk(newsk); 1329 newinet = inet_sk(newsk); 1330 newnp = inet6_sk(newsk); 1331 1332 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1333 1334 newnp->daddr = treq->rmt_addr; 1335 newnp->saddr = treq->loc_addr; 1336 newnp->rcv_saddr = treq->loc_addr; 1337 newsk->sk_bound_dev_if = treq->iif; 1338 1339 /* Now IPv6 options... 1340 1341 First: no IPv4 options. 1342 */ 1343 newinet->inet_opt = NULL; 1344 newnp->ipv6_ac_list = NULL; 1345 newnp->ipv6_fl_list = NULL; 1346 1347 /* Clone RX bits */ 1348 newnp->rxopt.all = np->rxopt.all; 1349 1350 /* Clone pktoptions received with SYN */ 1351 newnp->pktoptions = NULL; 1352 if (treq->pktopts != NULL) { 1353 newnp->pktoptions = skb_clone(treq->pktopts, GFP_ATOMIC); 1354 consume_skb(treq->pktopts); 1355 treq->pktopts = NULL; 1356 if (newnp->pktoptions) 1357 skb_set_owner_r(newnp->pktoptions, newsk); 1358 } 1359 newnp->opt = NULL; 1360 newnp->mcast_oif = inet6_iif(skb); 1361 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1362 newnp->rcv_tclass = ipv6_tclass(ipv6_hdr(skb)); 1363 1364 /* Clone native IPv6 options from listening socket (if any) 1365 1366 Yes, keeping reference count would be much more clever, 1367 but we make one more one thing there: reattach optmem 1368 to newsk. 1369 */ 1370 if (opt) { 1371 newnp->opt = ipv6_dup_options(newsk, opt); 1372 if (opt != np->opt) 1373 sock_kfree_s(sk, opt, opt->tot_len); 1374 } 1375 1376 inet_csk(newsk)->icsk_ext_hdr_len = 0; 1377 if (newnp->opt) 1378 inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen + 1379 newnp->opt->opt_flen); 1380 1381 tcp_mtup_init(newsk); 1382 tcp_sync_mss(newsk, dst_mtu(dst)); 1383 newtp->advmss = dst_metric_advmss(dst); 1384 if (tcp_sk(sk)->rx_opt.user_mss && 1385 tcp_sk(sk)->rx_opt.user_mss < newtp->advmss) 1386 newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; 1387 1388 tcp_initialize_rcv_mss(newsk); 1389 if (tcp_rsk(req)->snt_synack) 1390 tcp_valid_rtt_meas(newsk, 1391 tcp_time_stamp - tcp_rsk(req)->snt_synack); 1392 newtp->total_retrans = req->retrans; 1393 1394 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6; 1395 newinet->inet_rcv_saddr = LOOPBACK4_IPV6; 1396 1397 #ifdef CONFIG_TCP_MD5SIG 1398 /* Copy over the MD5 key from the original socket */ 1399 if ((key = tcp_v6_md5_do_lookup(sk, &newnp->daddr)) != NULL) { 1400 /* We're using one, so create a matching key 1401 * on the newsk structure. If we fail to get 1402 * memory, then we end up not copying the key 1403 * across. Shucks. 1404 */ 1405 tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newnp->daddr, 1406 AF_INET6, key->key, key->keylen, GFP_ATOMIC); 1407 } 1408 #endif 1409 1410 if (__inet_inherit_port(sk, newsk) < 0) { 1411 sock_put(newsk); 1412 goto out; 1413 } 1414 __inet6_hash(newsk, NULL); 1415 1416 return newsk; 1417 1418 out_overflow: 1419 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); 1420 out_nonewsk: 1421 if (opt && opt != np->opt) 1422 sock_kfree_s(sk, opt, opt->tot_len); 1423 dst_release(dst); 1424 out: 1425 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 1426 return NULL; 1427 } 1428 1429 static __sum16 tcp_v6_checksum_init(struct sk_buff *skb) 1430 { 1431 if (skb->ip_summed == CHECKSUM_COMPLETE) { 1432 if (!tcp_v6_check(skb->len, &ipv6_hdr(skb)->saddr, 1433 &ipv6_hdr(skb)->daddr, skb->csum)) { 1434 skb->ip_summed = CHECKSUM_UNNECESSARY; 1435 return 0; 1436 } 1437 } 1438 1439 skb->csum = ~csum_unfold(tcp_v6_check(skb->len, 1440 &ipv6_hdr(skb)->saddr, 1441 &ipv6_hdr(skb)->daddr, 0)); 1442 1443 if (skb->len <= 76) { 1444 return __skb_checksum_complete(skb); 1445 } 1446 return 0; 1447 } 1448 1449 /* The socket must have it's spinlock held when we get 1450 * here. 1451 * 1452 * We have a potential double-lock case here, so even when 1453 * doing backlog processing we use the BH locking scheme. 1454 * This is because we cannot sleep with the original spinlock 1455 * held. 1456 */ 1457 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) 1458 { 1459 struct ipv6_pinfo *np = inet6_sk(sk); 1460 struct tcp_sock *tp; 1461 struct sk_buff *opt_skb = NULL; 1462 1463 /* Imagine: socket is IPv6. IPv4 packet arrives, 1464 goes to IPv4 receive handler and backlogged. 1465 From backlog it always goes here. Kerboom... 1466 Fortunately, tcp_rcv_established and rcv_established 1467 handle them correctly, but it is not case with 1468 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK 1469 */ 1470 1471 if (skb->protocol == htons(ETH_P_IP)) 1472 return tcp_v4_do_rcv(sk, skb); 1473 1474 #ifdef CONFIG_TCP_MD5SIG 1475 if (tcp_v6_inbound_md5_hash (sk, skb)) 1476 goto discard; 1477 #endif 1478 1479 if (sk_filter(sk, skb)) 1480 goto discard; 1481 1482 /* 1483 * socket locking is here for SMP purposes as backlog rcv 1484 * is currently called with bh processing disabled. 1485 */ 1486 1487 /* Do Stevens' IPV6_PKTOPTIONS. 1488 1489 Yes, guys, it is the only place in our code, where we 1490 may make it not affecting IPv4. 1491 The rest of code is protocol independent, 1492 and I do not like idea to uglify IPv4. 1493 1494 Actually, all the idea behind IPV6_PKTOPTIONS 1495 looks not very well thought. For now we latch 1496 options, received in the last packet, enqueued 1497 by tcp. Feel free to propose better solution. 1498 --ANK (980728) 1499 */ 1500 if (np->rxopt.all) 1501 opt_skb = skb_clone(skb, GFP_ATOMIC); 1502 1503 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ 1504 sock_rps_save_rxhash(sk, skb); 1505 if (tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len)) 1506 goto reset; 1507 if (opt_skb) 1508 goto ipv6_pktoptions; 1509 return 0; 1510 } 1511 1512 if (skb->len < tcp_hdrlen(skb) || tcp_checksum_complete(skb)) 1513 goto csum_err; 1514 1515 if (sk->sk_state == TCP_LISTEN) { 1516 struct sock *nsk = tcp_v6_hnd_req(sk, skb); 1517 if (!nsk) 1518 goto discard; 1519 1520 /* 1521 * Queue it on the new socket if the new socket is active, 1522 * otherwise we just shortcircuit this and continue with 1523 * the new socket.. 1524 */ 1525 if(nsk != sk) { 1526 sock_rps_save_rxhash(nsk, skb); 1527 if (tcp_child_process(sk, nsk, skb)) 1528 goto reset; 1529 if (opt_skb) 1530 __kfree_skb(opt_skb); 1531 return 0; 1532 } 1533 } else 1534 sock_rps_save_rxhash(sk, skb); 1535 1536 if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len)) 1537 goto reset; 1538 if (opt_skb) 1539 goto ipv6_pktoptions; 1540 return 0; 1541 1542 reset: 1543 tcp_v6_send_reset(sk, skb); 1544 discard: 1545 if (opt_skb) 1546 __kfree_skb(opt_skb); 1547 kfree_skb(skb); 1548 return 0; 1549 csum_err: 1550 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS); 1551 goto discard; 1552 1553 1554 ipv6_pktoptions: 1555 /* Do you ask, what is it? 1556 1557 1. skb was enqueued by tcp. 1558 2. skb is added to tail of read queue, rather than out of order. 1559 3. socket is not in passive state. 1560 4. Finally, it really contains options, which user wants to receive. 1561 */ 1562 tp = tcp_sk(sk); 1563 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt && 1564 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { 1565 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo) 1566 np->mcast_oif = inet6_iif(opt_skb); 1567 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) 1568 np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit; 1569 if (np->rxopt.bits.rxtclass) 1570 np->rcv_tclass = ipv6_tclass(ipv6_hdr(skb)); 1571 if (ipv6_opt_accepted(sk, opt_skb)) { 1572 skb_set_owner_r(opt_skb, sk); 1573 opt_skb = xchg(&np->pktoptions, opt_skb); 1574 } else { 1575 __kfree_skb(opt_skb); 1576 opt_skb = xchg(&np->pktoptions, NULL); 1577 } 1578 } 1579 1580 kfree_skb(opt_skb); 1581 return 0; 1582 } 1583 1584 static int tcp_v6_rcv(struct sk_buff *skb) 1585 { 1586 const struct tcphdr *th; 1587 const struct ipv6hdr *hdr; 1588 struct sock *sk; 1589 int ret; 1590 struct net *net = dev_net(skb->dev); 1591 1592 if (skb->pkt_type != PACKET_HOST) 1593 goto discard_it; 1594 1595 /* 1596 * Count it even if it's bad. 1597 */ 1598 TCP_INC_STATS_BH(net, TCP_MIB_INSEGS); 1599 1600 if (!pskb_may_pull(skb, sizeof(struct tcphdr))) 1601 goto discard_it; 1602 1603 th = tcp_hdr(skb); 1604 1605 if (th->doff < sizeof(struct tcphdr)/4) 1606 goto bad_packet; 1607 if (!pskb_may_pull(skb, th->doff*4)) 1608 goto discard_it; 1609 1610 if (!skb_csum_unnecessary(skb) && tcp_v6_checksum_init(skb)) 1611 goto bad_packet; 1612 1613 th = tcp_hdr(skb); 1614 hdr = ipv6_hdr(skb); 1615 TCP_SKB_CB(skb)->seq = ntohl(th->seq); 1616 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + 1617 skb->len - th->doff*4); 1618 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); 1619 TCP_SKB_CB(skb)->when = 0; 1620 TCP_SKB_CB(skb)->ip_dsfield = ipv6_get_dsfield(hdr); 1621 TCP_SKB_CB(skb)->sacked = 0; 1622 1623 sk = __inet6_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest); 1624 if (!sk) 1625 goto no_tcp_socket; 1626 1627 process: 1628 if (sk->sk_state == TCP_TIME_WAIT) 1629 goto do_time_wait; 1630 1631 if (hdr->hop_limit < inet6_sk(sk)->min_hopcount) { 1632 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); 1633 goto discard_and_relse; 1634 } 1635 1636 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 1637 goto discard_and_relse; 1638 1639 if (sk_filter(sk, skb)) 1640 goto discard_and_relse; 1641 1642 skb->dev = NULL; 1643 1644 bh_lock_sock_nested(sk); 1645 ret = 0; 1646 if (!sock_owned_by_user(sk)) { 1647 #ifdef CONFIG_NET_DMA 1648 struct tcp_sock *tp = tcp_sk(sk); 1649 if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list) 1650 tp->ucopy.dma_chan = net_dma_find_channel(); 1651 if (tp->ucopy.dma_chan) 1652 ret = tcp_v6_do_rcv(sk, skb); 1653 else 1654 #endif 1655 { 1656 if (!tcp_prequeue(sk, skb)) 1657 ret = tcp_v6_do_rcv(sk, skb); 1658 } 1659 } else if (unlikely(sk_add_backlog(sk, skb, 1660 sk->sk_rcvbuf + sk->sk_sndbuf))) { 1661 bh_unlock_sock(sk); 1662 NET_INC_STATS_BH(net, LINUX_MIB_TCPBACKLOGDROP); 1663 goto discard_and_relse; 1664 } 1665 bh_unlock_sock(sk); 1666 1667 sock_put(sk); 1668 return ret ? -1 : 0; 1669 1670 no_tcp_socket: 1671 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 1672 goto discard_it; 1673 1674 if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) { 1675 bad_packet: 1676 TCP_INC_STATS_BH(net, TCP_MIB_INERRS); 1677 } else { 1678 tcp_v6_send_reset(NULL, skb); 1679 } 1680 1681 discard_it: 1682 1683 /* 1684 * Discard frame 1685 */ 1686 1687 kfree_skb(skb); 1688 return 0; 1689 1690 discard_and_relse: 1691 sock_put(sk); 1692 goto discard_it; 1693 1694 do_time_wait: 1695 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 1696 inet_twsk_put(inet_twsk(sk)); 1697 goto discard_it; 1698 } 1699 1700 if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) { 1701 TCP_INC_STATS_BH(net, TCP_MIB_INERRS); 1702 inet_twsk_put(inet_twsk(sk)); 1703 goto discard_it; 1704 } 1705 1706 switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { 1707 case TCP_TW_SYN: 1708 { 1709 struct sock *sk2; 1710 1711 sk2 = inet6_lookup_listener(dev_net(skb->dev), &tcp_hashinfo, 1712 &ipv6_hdr(skb)->daddr, 1713 ntohs(th->dest), inet6_iif(skb)); 1714 if (sk2 != NULL) { 1715 struct inet_timewait_sock *tw = inet_twsk(sk); 1716 inet_twsk_deschedule(tw, &tcp_death_row); 1717 inet_twsk_put(tw); 1718 sk = sk2; 1719 goto process; 1720 } 1721 /* Fall through to ACK */ 1722 } 1723 case TCP_TW_ACK: 1724 tcp_v6_timewait_ack(sk, skb); 1725 break; 1726 case TCP_TW_RST: 1727 goto no_tcp_socket; 1728 case TCP_TW_SUCCESS:; 1729 } 1730 goto discard_it; 1731 } 1732 1733 static struct inet_peer *tcp_v6_get_peer(struct sock *sk, bool *release_it) 1734 { 1735 struct rt6_info *rt = (struct rt6_info *) __sk_dst_get(sk); 1736 struct ipv6_pinfo *np = inet6_sk(sk); 1737 struct inet_peer *peer; 1738 1739 if (!rt || 1740 !ipv6_addr_equal(&np->daddr, &rt->rt6i_dst.addr)) { 1741 peer = inet_getpeer_v6(&np->daddr, 1); 1742 *release_it = true; 1743 } else { 1744 if (!rt->rt6i_peer) 1745 rt6_bind_peer(rt, 1); 1746 peer = rt->rt6i_peer; 1747 *release_it = false; 1748 } 1749 1750 return peer; 1751 } 1752 1753 static void *tcp_v6_tw_get_peer(struct sock *sk) 1754 { 1755 const struct inet6_timewait_sock *tw6 = inet6_twsk(sk); 1756 const struct inet_timewait_sock *tw = inet_twsk(sk); 1757 1758 if (tw->tw_family == AF_INET) 1759 return tcp_v4_tw_get_peer(sk); 1760 1761 return inet_getpeer_v6(&tw6->tw_v6_daddr, 1); 1762 } 1763 1764 static struct timewait_sock_ops tcp6_timewait_sock_ops = { 1765 .twsk_obj_size = sizeof(struct tcp6_timewait_sock), 1766 .twsk_unique = tcp_twsk_unique, 1767 .twsk_destructor= tcp_twsk_destructor, 1768 .twsk_getpeer = tcp_v6_tw_get_peer, 1769 }; 1770 1771 static const struct inet_connection_sock_af_ops ipv6_specific = { 1772 .queue_xmit = inet6_csk_xmit, 1773 .send_check = tcp_v6_send_check, 1774 .rebuild_header = inet6_sk_rebuild_header, 1775 .conn_request = tcp_v6_conn_request, 1776 .syn_recv_sock = tcp_v6_syn_recv_sock, 1777 .get_peer = tcp_v6_get_peer, 1778 .net_header_len = sizeof(struct ipv6hdr), 1779 .net_frag_header_len = sizeof(struct frag_hdr), 1780 .setsockopt = ipv6_setsockopt, 1781 .getsockopt = ipv6_getsockopt, 1782 .addr2sockaddr = inet6_csk_addr2sockaddr, 1783 .sockaddr_len = sizeof(struct sockaddr_in6), 1784 .bind_conflict = inet6_csk_bind_conflict, 1785 #ifdef CONFIG_COMPAT 1786 .compat_setsockopt = compat_ipv6_setsockopt, 1787 .compat_getsockopt = compat_ipv6_getsockopt, 1788 #endif 1789 }; 1790 1791 #ifdef CONFIG_TCP_MD5SIG 1792 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific = { 1793 .md5_lookup = tcp_v6_md5_lookup, 1794 .calc_md5_hash = tcp_v6_md5_hash_skb, 1795 .md5_parse = tcp_v6_parse_md5_keys, 1796 }; 1797 #endif 1798 1799 /* 1800 * TCP over IPv4 via INET6 API 1801 */ 1802 1803 static const struct inet_connection_sock_af_ops ipv6_mapped = { 1804 .queue_xmit = ip_queue_xmit, 1805 .send_check = tcp_v4_send_check, 1806 .rebuild_header = inet_sk_rebuild_header, 1807 .conn_request = tcp_v6_conn_request, 1808 .syn_recv_sock = tcp_v6_syn_recv_sock, 1809 .get_peer = tcp_v4_get_peer, 1810 .net_header_len = sizeof(struct iphdr), 1811 .setsockopt = ipv6_setsockopt, 1812 .getsockopt = ipv6_getsockopt, 1813 .addr2sockaddr = inet6_csk_addr2sockaddr, 1814 .sockaddr_len = sizeof(struct sockaddr_in6), 1815 .bind_conflict = inet6_csk_bind_conflict, 1816 #ifdef CONFIG_COMPAT 1817 .compat_setsockopt = compat_ipv6_setsockopt, 1818 .compat_getsockopt = compat_ipv6_getsockopt, 1819 #endif 1820 }; 1821 1822 #ifdef CONFIG_TCP_MD5SIG 1823 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = { 1824 .md5_lookup = tcp_v4_md5_lookup, 1825 .calc_md5_hash = tcp_v4_md5_hash_skb, 1826 .md5_parse = tcp_v6_parse_md5_keys, 1827 }; 1828 #endif 1829 1830 /* NOTE: A lot of things set to zero explicitly by call to 1831 * sk_alloc() so need not be done here. 1832 */ 1833 static int tcp_v6_init_sock(struct sock *sk) 1834 { 1835 struct inet_connection_sock *icsk = inet_csk(sk); 1836 1837 tcp_init_sock(sk); 1838 1839 icsk->icsk_af_ops = &ipv6_specific; 1840 1841 #ifdef CONFIG_TCP_MD5SIG 1842 tcp_sk(sk)->af_specific = &tcp_sock_ipv6_specific; 1843 #endif 1844 1845 return 0; 1846 } 1847 1848 static void tcp_v6_destroy_sock(struct sock *sk) 1849 { 1850 tcp_v4_destroy_sock(sk); 1851 inet6_destroy_sock(sk); 1852 } 1853 1854 #ifdef CONFIG_PROC_FS 1855 /* Proc filesystem TCPv6 sock list dumping. */ 1856 static void get_openreq6(struct seq_file *seq, 1857 const struct sock *sk, struct request_sock *req, int i, int uid) 1858 { 1859 int ttd = req->expires - jiffies; 1860 const struct in6_addr *src = &inet6_rsk(req)->loc_addr; 1861 const struct in6_addr *dest = &inet6_rsk(req)->rmt_addr; 1862 1863 if (ttd < 0) 1864 ttd = 0; 1865 1866 seq_printf(seq, 1867 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1868 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n", 1869 i, 1870 src->s6_addr32[0], src->s6_addr32[1], 1871 src->s6_addr32[2], src->s6_addr32[3], 1872 ntohs(inet_rsk(req)->loc_port), 1873 dest->s6_addr32[0], dest->s6_addr32[1], 1874 dest->s6_addr32[2], dest->s6_addr32[3], 1875 ntohs(inet_rsk(req)->rmt_port), 1876 TCP_SYN_RECV, 1877 0,0, /* could print option size, but that is af dependent. */ 1878 1, /* timers active (only the expire timer) */ 1879 jiffies_to_clock_t(ttd), 1880 req->retrans, 1881 uid, 1882 0, /* non standard timer */ 1883 0, /* open_requests have no inode */ 1884 0, req); 1885 } 1886 1887 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) 1888 { 1889 const struct in6_addr *dest, *src; 1890 __u16 destp, srcp; 1891 int timer_active; 1892 unsigned long timer_expires; 1893 const struct inet_sock *inet = inet_sk(sp); 1894 const struct tcp_sock *tp = tcp_sk(sp); 1895 const struct inet_connection_sock *icsk = inet_csk(sp); 1896 const struct ipv6_pinfo *np = inet6_sk(sp); 1897 1898 dest = &np->daddr; 1899 src = &np->rcv_saddr; 1900 destp = ntohs(inet->inet_dport); 1901 srcp = ntohs(inet->inet_sport); 1902 1903 if (icsk->icsk_pending == ICSK_TIME_RETRANS) { 1904 timer_active = 1; 1905 timer_expires = icsk->icsk_timeout; 1906 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { 1907 timer_active = 4; 1908 timer_expires = icsk->icsk_timeout; 1909 } else if (timer_pending(&sp->sk_timer)) { 1910 timer_active = 2; 1911 timer_expires = sp->sk_timer.expires; 1912 } else { 1913 timer_active = 0; 1914 timer_expires = jiffies; 1915 } 1916 1917 seq_printf(seq, 1918 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1919 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %lu %lu %u %u %d\n", 1920 i, 1921 src->s6_addr32[0], src->s6_addr32[1], 1922 src->s6_addr32[2], src->s6_addr32[3], srcp, 1923 dest->s6_addr32[0], dest->s6_addr32[1], 1924 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1925 sp->sk_state, 1926 tp->write_seq-tp->snd_una, 1927 (sp->sk_state == TCP_LISTEN) ? sp->sk_ack_backlog : (tp->rcv_nxt - tp->copied_seq), 1928 timer_active, 1929 jiffies_to_clock_t(timer_expires - jiffies), 1930 icsk->icsk_retransmits, 1931 sock_i_uid(sp), 1932 icsk->icsk_probes_out, 1933 sock_i_ino(sp), 1934 atomic_read(&sp->sk_refcnt), sp, 1935 jiffies_to_clock_t(icsk->icsk_rto), 1936 jiffies_to_clock_t(icsk->icsk_ack.ato), 1937 (icsk->icsk_ack.quick << 1 ) | icsk->icsk_ack.pingpong, 1938 tp->snd_cwnd, 1939 tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh 1940 ); 1941 } 1942 1943 static void get_timewait6_sock(struct seq_file *seq, 1944 struct inet_timewait_sock *tw, int i) 1945 { 1946 const struct in6_addr *dest, *src; 1947 __u16 destp, srcp; 1948 const struct inet6_timewait_sock *tw6 = inet6_twsk((struct sock *)tw); 1949 int ttd = tw->tw_ttd - jiffies; 1950 1951 if (ttd < 0) 1952 ttd = 0; 1953 1954 dest = &tw6->tw_v6_daddr; 1955 src = &tw6->tw_v6_rcv_saddr; 1956 destp = ntohs(tw->tw_dport); 1957 srcp = ntohs(tw->tw_sport); 1958 1959 seq_printf(seq, 1960 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1961 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n", 1962 i, 1963 src->s6_addr32[0], src->s6_addr32[1], 1964 src->s6_addr32[2], src->s6_addr32[3], srcp, 1965 dest->s6_addr32[0], dest->s6_addr32[1], 1966 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1967 tw->tw_substate, 0, 0, 1968 3, jiffies_to_clock_t(ttd), 0, 0, 0, 0, 1969 atomic_read(&tw->tw_refcnt), tw); 1970 } 1971 1972 static int tcp6_seq_show(struct seq_file *seq, void *v) 1973 { 1974 struct tcp_iter_state *st; 1975 1976 if (v == SEQ_START_TOKEN) { 1977 seq_puts(seq, 1978 " sl " 1979 "local_address " 1980 "remote_address " 1981 "st tx_queue rx_queue tr tm->when retrnsmt" 1982 " uid timeout inode\n"); 1983 goto out; 1984 } 1985 st = seq->private; 1986 1987 switch (st->state) { 1988 case TCP_SEQ_STATE_LISTENING: 1989 case TCP_SEQ_STATE_ESTABLISHED: 1990 get_tcp6_sock(seq, v, st->num); 1991 break; 1992 case TCP_SEQ_STATE_OPENREQ: 1993 get_openreq6(seq, st->syn_wait_sk, v, st->num, st->uid); 1994 break; 1995 case TCP_SEQ_STATE_TIME_WAIT: 1996 get_timewait6_sock(seq, v, st->num); 1997 break; 1998 } 1999 out: 2000 return 0; 2001 } 2002 2003 static const struct file_operations tcp6_afinfo_seq_fops = { 2004 .owner = THIS_MODULE, 2005 .open = tcp_seq_open, 2006 .read = seq_read, 2007 .llseek = seq_lseek, 2008 .release = seq_release_net 2009 }; 2010 2011 static struct tcp_seq_afinfo tcp6_seq_afinfo = { 2012 .name = "tcp6", 2013 .family = AF_INET6, 2014 .seq_fops = &tcp6_afinfo_seq_fops, 2015 .seq_ops = { 2016 .show = tcp6_seq_show, 2017 }, 2018 }; 2019 2020 int __net_init tcp6_proc_init(struct net *net) 2021 { 2022 return tcp_proc_register(net, &tcp6_seq_afinfo); 2023 } 2024 2025 void tcp6_proc_exit(struct net *net) 2026 { 2027 tcp_proc_unregister(net, &tcp6_seq_afinfo); 2028 } 2029 #endif 2030 2031 struct proto tcpv6_prot = { 2032 .name = "TCPv6", 2033 .owner = THIS_MODULE, 2034 .close = tcp_close, 2035 .connect = tcp_v6_connect, 2036 .disconnect = tcp_disconnect, 2037 .accept = inet_csk_accept, 2038 .ioctl = tcp_ioctl, 2039 .init = tcp_v6_init_sock, 2040 .destroy = tcp_v6_destroy_sock, 2041 .shutdown = tcp_shutdown, 2042 .setsockopt = tcp_setsockopt, 2043 .getsockopt = tcp_getsockopt, 2044 .recvmsg = tcp_recvmsg, 2045 .sendmsg = tcp_sendmsg, 2046 .sendpage = tcp_sendpage, 2047 .backlog_rcv = tcp_v6_do_rcv, 2048 .hash = tcp_v6_hash, 2049 .unhash = inet_unhash, 2050 .get_port = inet_csk_get_port, 2051 .enter_memory_pressure = tcp_enter_memory_pressure, 2052 .sockets_allocated = &tcp_sockets_allocated, 2053 .memory_allocated = &tcp_memory_allocated, 2054 .memory_pressure = &tcp_memory_pressure, 2055 .orphan_count = &tcp_orphan_count, 2056 .sysctl_wmem = sysctl_tcp_wmem, 2057 .sysctl_rmem = sysctl_tcp_rmem, 2058 .max_header = MAX_TCP_HEADER, 2059 .obj_size = sizeof(struct tcp6_sock), 2060 .slab_flags = SLAB_DESTROY_BY_RCU, 2061 .twsk_prot = &tcp6_timewait_sock_ops, 2062 .rsk_prot = &tcp6_request_sock_ops, 2063 .h.hashinfo = &tcp_hashinfo, 2064 .no_autobind = true, 2065 #ifdef CONFIG_COMPAT 2066 .compat_setsockopt = compat_tcp_setsockopt, 2067 .compat_getsockopt = compat_tcp_getsockopt, 2068 #endif 2069 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM 2070 .proto_cgroup = tcp_proto_cgroup, 2071 #endif 2072 }; 2073 2074 static const struct inet6_protocol tcpv6_protocol = { 2075 .handler = tcp_v6_rcv, 2076 .err_handler = tcp_v6_err, 2077 .gso_send_check = tcp_v6_gso_send_check, 2078 .gso_segment = tcp_tso_segment, 2079 .gro_receive = tcp6_gro_receive, 2080 .gro_complete = tcp6_gro_complete, 2081 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 2082 }; 2083 2084 static struct inet_protosw tcpv6_protosw = { 2085 .type = SOCK_STREAM, 2086 .protocol = IPPROTO_TCP, 2087 .prot = &tcpv6_prot, 2088 .ops = &inet6_stream_ops, 2089 .no_check = 0, 2090 .flags = INET_PROTOSW_PERMANENT | 2091 INET_PROTOSW_ICSK, 2092 }; 2093 2094 static int __net_init tcpv6_net_init(struct net *net) 2095 { 2096 return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6, 2097 SOCK_RAW, IPPROTO_TCP, net); 2098 } 2099 2100 static void __net_exit tcpv6_net_exit(struct net *net) 2101 { 2102 inet_ctl_sock_destroy(net->ipv6.tcp_sk); 2103 } 2104 2105 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list) 2106 { 2107 inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6); 2108 } 2109 2110 static struct pernet_operations tcpv6_net_ops = { 2111 .init = tcpv6_net_init, 2112 .exit = tcpv6_net_exit, 2113 .exit_batch = tcpv6_net_exit_batch, 2114 }; 2115 2116 int __init tcpv6_init(void) 2117 { 2118 int ret; 2119 2120 ret = inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP); 2121 if (ret) 2122 goto out; 2123 2124 /* register inet6 protocol */ 2125 ret = inet6_register_protosw(&tcpv6_protosw); 2126 if (ret) 2127 goto out_tcpv6_protocol; 2128 2129 ret = register_pernet_subsys(&tcpv6_net_ops); 2130 if (ret) 2131 goto out_tcpv6_protosw; 2132 out: 2133 return ret; 2134 2135 out_tcpv6_protocol: 2136 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 2137 out_tcpv6_protosw: 2138 inet6_unregister_protosw(&tcpv6_protosw); 2139 goto out; 2140 } 2141 2142 void tcpv6_exit(void) 2143 { 2144 unregister_pernet_subsys(&tcpv6_net_ops); 2145 inet6_unregister_protosw(&tcpv6_protosw); 2146 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 2147 } 2148